Wallace admits that BioWare's vision for companions has been augmented based on how players actually used the NPCs during gameplay. The team added passive and active controls over companions. In fact, if a player only wishes to control some companion actions but not others, BioWare provided ways to do that, too.
We also know that sometimes groups can be split up. Wallace explains how SWTOR works around that:
If a player leaves the group or its proximity, to travel to a vendor for instance, he is able to summon his companion for the journey. Upon reentering proximity of the group, the companion is automatically dismissed. The remaining group can temporarily substitute the missing player with one of their companions if desired.Companions are a staple in BioWare games. Developers promise to continue to make the companion gaming experience better -- meeting or exceeding your expectations.